The present invention relates to a structure in an article for personal care like diapers, training pants, absorbent underpants, adult incontinence products, bandages and feminine hygiene products, which can accept a surge of liquid.
Personal care articles include such items as diapers, training pants, incontinence garments and devices, bandages and feminine hygiene products such as sanitary napkins, panty-liners and tampons and the like. The most basic design of all such articles typically includes a body side liner, an outercover and an absorbent core disposed between the body side liner and the outercover.
Feminine hygiene products like sanitary napkins, for example, have absorbent cores which have traditionally been designed to take in a thick, slow flowing fluid. Menstruating women, however, frequently complain of experiencing sudden gushes or surges of menstrual discharge which exits the body as a high volume, short delivery time, insult of fluid. An absorbent core designed to handle, slow moving flow usually has too small a pore structure to rapidly take in these gushes or limited surges of fluid and, as a result, fluid pooling or puddling on the product surface may result. Pooling on the surface can result in runoff or staining of the clothing and is unacceptable to the wearer. Alternatively, absorbent material(s) which have a sufficiently large pore structure to rapidly absorb gushes usually cannot redistribute that fluid to the extreme ends of the product, thus resulting in surge fluid accumulating in the center part of the pad where side leg pressure can cause leaks.
It is an object of this invention, therefore, to provide an absorbent structure which can rapidly take in sudden surges or gushes of fluid, pull the fluid away from the upper part of the absorbent to achieve a feeling of dryness for the user, redistribute that fluid along the entire length of the structure and release that fluid to other subsequent absorbent layers.
The objects of the invention are achieved by a fluid management material for personal care products which distributes artificial menses according to the gush/distribution test taught herein such that it has a distribution ratio of at least about 0.06.
Its preferred that the fluid management material be part of an absorbent materials system having a first fibrous layer, a middle layer adjacent the first layer having hydrophilic oriented surface fibers, and a second fibrous layer adjacent the middle layer. The density of the first layer is between about 0.02 and 0.14 g/cc. The density of the second layer is greater than the first layer and the second layer is preferably homogeneous in its resistance to liquid flow.
In a personal care product configuration the oriented surface fibers result in a distribution ratio of at least 0.06. It is preferred that products incorporating this invention have a minimum of 2.0 square meters of fiber surface area per product in the oriented surface fibers layer arranged in at least one zone of oriented surface fibers where the zone is at most 20 mm wide and the basis weight is at least 50 gsm.